Why you shouldn’t align html justify
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Here’s an example of justified website text. As you can see, the text is aligned to both the left margin and right margins, meaning that each line will be the same length.

Martin says... Don't Justify Align
I was recently asked by one of my WordPress clients to justify fully the text on their website rather than to align left. Justification (or full alignment or double justification) means that each line in your web page is the same length (except perhaps for the last line), with the text on those lines being spread out to meet a uniform line width and to align with both the left and right margins.
The html code (or attribute) to achieve this (for those of you who are interested) is align=”justify”.
I advised my client against justifying the text on their web page. I think that most website readers prefer to have their text set out in fairly narrow columns, and with the text aligned left. This makes it easier to read.
Justified Alignment is is actually non-standard for the web, and the W3C standards commitee state the following :
Of course, it’s up to you as a website owner to make the final decision on the text layout and other styles on your site, and don’t forget that text alignment has worked successfully for newspapers for many decades.
The wider the width of the paragraphs, and the better the justification algorithm, the less “rivers of white” is a problem. The IE “newspaper” form of justification is particularly good.
I find that with no white space at the left margin the page is difficult to read,as the letters look as though they bleed into the border line. I usually wont bother reading it at all. I find if I view a page in ‘no style’ rather than default, it looks better.